check.js

    var ctx=$("#canvas")[0].getContext("2d")
    
    var fillZero=function(num,length){
        num=num.toString();
        var str="";
        for(var i=0,n=length-num.length;i<n;i++){
            str+="0";
        }
        return str+num;
    }
    function run(){
        /**
         * @param {string} time 形式为 1.1.2.9的数组
         */
        var drawTime=function(time){
            var bai=localStorage['bai'];

            var a=time[0],
            b=time[1],
            c=time[2],
            d=time[3]
            ctx.clearRect(0,0, 19, 19)
            ctx.drawImage(bai==1?imgbai[a]:img[a],0,0,9,9);
            ctx.drawImage(bai==1?imgbai[b]:img[b],10,0,9,9);
            ctx.drawImage(bai==1?imgbai[c]:img[c],0,10,9,9);
            ctx.drawImage(bai==1?imgbai[d]:img[d],10,10,9,9);
            chrome.browserAction.setIcon({
                path:$("canvas")[0].toDataURL()
            })
        }
       
        drawTime([1,2,3,4])
        
        
        setInterval(function(){
            var arr_2=[
                localStorage["time1"]||"hour",
                localStorage["time2"]||"minute"
            ]
       
            var time=new Date();
            var data={
                hour:fillZero(time.getHours(),2),
                minute:fillZero(time.getMinutes(),2),
                sec:fillZero(time.getSeconds(),2),
                month:fillZero(time.getMonth()+1,2),
                date:fillZero(time.getDate(),2),
                year:fillZero(time.getFullYear(),4).substr(2,4)
            }
           
            var data1=data[arr_2[0]],data2=data[arr_2[1]]
            drawTime([data1.charAt(0),data1.charAt(1),data2.charAt(0),data2.charAt(1)])
        },100)

    }


    var checkLoad=function(){
        count--;
        if(count==0){
            run();
        }
    }
    var img=new Array(10),
    count=20;
    var imgcount=0;
    for(var i=0;i<10;i++){
        img[i]=new Image();
        
            img[i].src="img/"+i+".png"
        
        img[i].onload=checkLoad;
    }
    var imgbai=new Array(10)
    var imgcountbai=0;
    for(var i=0;i<10;i++){
        imgbai[i]=new Image();
  
            imgbai[i].src="img/"+i+"-w.png"
       
        imgbai[i].onload=checkLoad;
    }